Ethyl Corporation

Albemarle Corporation

James E Boone

David W Owens

Robert E Farritor

Wesley D Blank

John C Prindle

Robert H Allen

Ronald L Shubkin

Phillip R Beaver

Eric W Liimatta

Dixie E Goins

David L Shelton

Steven P Diefenbach

Kaung-Far Lin

Cecil P Loechelt

Joseph A Bossier, Iii

Douglas M Richards

Brian Kneale

Jason G Jones

Michael D Matthews

Max K Mortensen

James Dee Palmer

Michael W Easson

Sharon D Booth McGee

Process of producing self-supported catalysts

A mixture comprised of about 60-85% of 2,4-toluenediamine (2,4-TDA) and about 15-40% of 2,6-toluenediamine (2,6-TDA) is melted, the temperature of the mixture is lowered to a 2,4-TDA nucleation temperature, and the temperature of the mixture is gradually reduced from the nucleation temperature to about 65 to about 70&deg; C. The resultant mixture is in the form of a solids phase enriched in 2,4-TDA, and a novel and useful liquid phase enriched in 2,6-TDA. These phases are separated. Preferably the solids are further purified by &ldquo;sweating&rdquo; them and removing the sweated liquid impurities. The sweated liquid can be recycled together with another charge of a mixture comprised of 2,4-TDA and 2,6-TDA. 2,4-TDA can be produced with a purity of 96-99%.

Separation of 2,4-toluenediamine from an isomeric mixture of toluenediamines

A highly efficient method of producing alkyl mercaptan and/or dialkyl monosulfides which involves employing carbon dioxide as an internal coolant is described. Only negligible amounts of carbonyl sulfide were formed. In addition, relatively easy separation of carbon dioxide from the reaction mixture facilitates an efficient coolant recycle process, giving a simple and effective mode of temperature control.

Method for producing alkyl mercaptans and/or dialkyl monosulfides

A cleaning process suitable for both mild and aggressive applications employs non-flammable, non-corrosive and environmentally friendly, fluorinated hydrobromocarbon solvent based cleaning compositions.

Fluorinated hydrobromocarbon solvent cleaning process and composition

A process for cleaning movie film, and especially cellulose acetate based polymer film, without causing film damage, comprises immersing the film into a cleaning solvent composition which comprises one or more halogenated hydrobromocarbons having from 1 to 3 carbons, from 1 to 3 bromine atoms and at least one chlorine or fluorine atom, such as 3-bromo-1,1,1-trifluoropropane, removing the film from the solvent and drying the film.

Movie film cleaning process using halogenated hydrobromocarbon solvents

The hydrogen content of polysilicon can be reduced by heat treatment. The process is preferably conducted on polysilicon particles in bead-like form produced by chemical vapor deposition in a fluidized bed. The heat treatment is preferably conducted at a temperature of 1020.degree.-1200.degree. C. for a time from about 6 hours to about 1 hour sufficient to reduce the hydrogen content, and insufficient to cause agglomeration of the particles being treated. In order to reduce the tendency of particles to agglomerate at the process temperature employed, the particle bed is preferably maintained in motion during the dehydrogenation. The products produced by the process can have a hydrogen content of 30 ppma or less. These improved products can be used to produce monocrystalline silicon for the production of semiconductor devices.

Process for preparing polysilicon with diminished hydrogen content by

An apparatus and process for maintaining the purity of solid/granular product and dispensing high purity granular product from a vessel. A noncontaminating surface is provided by a cup, cylinder, or other structure having a surface of silicon, silicon carbide, silicon nitride, sialon, or similar materials and preferably operates as an angle of repose valve in a pressurized system to prevent contamination by undue contact of the high purity product with conventional gastight valves such as ball valves, butterfly valves, pinch valves, etc.

Angle of repose valve

A process for continuously preparing silane and a coproduct by reacting a metal hydride such as NaAlH.sub.4 with a silicon halide such as SiF.sub.4, utilizing, in conducting the reaction, equipment which includes, in series, a primary reactor, a secondary reactor and a separation zone. The metal hydride is reacted in the first reactor with less than a stoichiometric amount of the silicon halide, and the unreacted metal hydride is then passed to the second reactor wherein the remainder of the hydride is reacted in the secondary reactor, in which a stoichiometric excess of the silicon halide is added. The rate of silicon halide or metal hydride addition is governed by a temperature differential feed back from the reaction in the secondary reactor so that overall a stoichiometric or substantially stoichiometric operation is achieved. Techniques are also disclosed for splitting the silicon halide feed between the liquid and vapor phases of the secondary reactor to eliminate the hazard of combustible mixtures, and, with variable speed agitation of the liquid, to control the mass transfer characteristics of the reaction. Also, consistant kinetics result from control of residence time by varying the liquid level in the secondary reactor as related to the halide or hydride mass flow rates. These improvements conserve resources, provides improved coproduct and reduce costs.

Process for preparation of silane

Production of silicon

An apparatus for maintaining the purity of solid/granular product and dispensing high purity granular product from a vessel. A noncontaminating surface is provided by a cup, cylinder, or other structure having a surface of silicon, silicon carbide, silicon nitride, sialon, or similar materials and preferably operates as an angle of repose valve in a pressurized system to prevent contamination by undue contact of the high purity product with conventional gastight valves such as ball valves, butterfly valves, pinch valves, etc.

Fluidized bed reactor

Growing community of inventors

Baton Rouge, LA, United States of America

James E Boone